Effect of different shielding gases on microstructure and mechanical properties of non-magnetic steel 20Mn23AlV welded joint

不同保护气体对无磁钢20Mn23AlV焊接接头组织及力学性能的影响 Effect of different shielding gases on microstructure and mechanical properties of non-magnetic steel 20Mn23AlV welded joint 陈丽园 CHEN Liyuan 1 first-author 郭瑞青 GUO Ruiqing 1 郝晓卫 HAO Xiaowei 1 侯金柱 HOU Jinzhu 1 孙逸凡 SUN Yifan 2 corresp 1377748054@qq.com 中车唐山机车车辆有限公司 中车唐山机车车辆有限公司 CRRC Tangshan Co.,Ltd. CRRC Tangshan Co.,Ltd. 大连交通大学 大连交通大学 Dalian Jiaotong University Dalian Jiaotong University 采用φ（Ar）97%+φ（CO 2 ）3%和φ（Ar）97.5%+φ（CO 2 ）2.5%两种保护气体对厚12 mm的20Mn23AlV无磁钢板进行焊接,对比不同保护气体下20Mn23AlV无磁钢焊接接头的显微组织及力学性能。结果表明:采用φ（Ar）97.5%+φ（CO 2 ）2.5%保护气体焊接的试板焊缝表面成形更优,焊缝内部气孔少;两种保护气体下的焊接接头都具有良好的塑性、韧性及抗拉强度,φ（Ar）97.5%+φ（CO 2 ）2.5%保护气体下的接头的抗拉强度略大,焊缝组织为白色的奥氏体基体+δ铁素体。综合来看,采用φ（Ar）97.5%+φ（CO 2 ）2.5%保护气体更为合理,满足无磁钢焊接生产要求。 The microstructure and mechanical properties of 20Mn23AlV non-magnetic steel plate with thickness of 12 mm are compared by welding with different shielding gases.The results show that the appearance of weld surface of the test plate welded with 97.5% Ar+2.5% CO 2 shielding gas is better,and there are few pores in the weld.The welded joints with two kinds of shielding gases have good plasticity,toughness and tensile strength.The microstructure of the weld is white austenite matrix+δ ferrite. Using 97.5%Ar+2.5%CO 2 shielding gas is reasonable and can meet the non-magnetic steel welding production requirements. 无磁钢20Mn23AlV 焊接接头 力学性能 保护气体 TG407 2022-03-08 4 51